UC-NRLF 


SB 


573 


in 


oo 


o 


LIBRARY 

OF    THE 

UNIVERSITY  OF  CALIFORNIA. 

Class 


m 


"The  simplest  natural  objects  have  bearings  which  calculation  does  not 
touch,  and  appearances  and  relations  which  definition  fails  to  include." 


General   Specifications 


FOB 


Steel  Roofs  and  Buildings. 


FOURTH    REVISED   EDITION. 

With  Tables. 


19OI 


CHARLES   EVAN   FOWLER, 

M.  Am.  Soc.  0    E. 


N*v 

fc&UFQf^ 


Diagram. 


£*y££: 

GENERAL    SP&GIFIGftTIONS    FOR   STEEL 
ROOFS   flND   BUILDINGS. 

CHARLES  EVAN  FOWLER,  M.  AM.  Soc.  C.  E. 
FOURTH  REVISED  EDITION 

1899- 
GENERAL  DESCRIPTION. 

1.  The  structure  shall  be  of  the  general  outline  and  dimen- 
sions shown  on  the  attached  diagram,  which  gives  the  principal 
dimensions  and  all  the  principal  data.     (2,  72.) 

2.  The  sizes  and  sections  of  all   members,   together  with  the 
strains    which    come    upon    them,  shall   be   marked   in   their 
proper  places  upon  a  strain  sheet,  and  submitted  with   proposal. 

(X  72.) 

3.  The  height  of  the  building  shall  mean  the  distance   from  clearances, 
top  of  masonry  to  under  -side  of    bottom  chord  of  truss.      The 

width  and  length  of  building  shall  mean  the  extreme  distance 
out  to  out  of  framing  or  sheeting. 

4.  The  pitch  of  roof  shall  generally  be  one  fourth.     (6.) 

LOADS. 
The  trusses  shall  be  figured  to  carry  the  following  loads: 


5.    SNOW  LOADS. 

PITCH  OF  ROOF. 

LOCATION. 

1-2 

i-3 

1-4 

i-5 

1-6 

Southern  States  and  Pacific  Slope  . 
Central  States      * 

O 
O 
O 
O 
n 

o 

7 
10 

10 
12 

o 

15 

20 
2O 
2C 

O 
22 
27 

35 

17 

o 

30 

35 
45 

CO 

Rocky  Mountain  States     .... 
New  England  States  ...... 

Northwest  States 

Snow  Load. 


Pounds  per  hor.  sq.  foot. 
6.    The  wind  pressure  on  trusses  in   pounds  per  square  foot   wind  Load, 
shall  be  taken  from  the  following  table: 


Pitch  Vertical       Horizontal 

i-2=45°oo'  19  19 

i-3  =  33°4i'  17  12 

i-4=26°34'  15  8 

i-5  =  2i°48'  13  6 

i-6=i8°26'  n  4 

7.     The  sides  and  ends  of  buildings  shall 

uniformly  distributed  wind  load  of  2O  pounds 

of  exposed    surtace    when  20  feet  or    less 


Normal. 
27 

22 

18 
15 
13  (70 

be  figured  for  a 
per  square    foot 
to  the  eaves;   30 
the 


pounds  per  square  foot  of  exposed  surface  when  60  feet  to 
eaves,  and  proportionately  for  intermediate  heights.     (6.) 


ering 


Weight  of  cov-    8.     The   weight  of  covering  may  be   taken  as  .follows:     Cor- 
rugated iron  laid,  black  and  painted,  per  square  foot: 
No.  27        26        24        22        20        18         16 

.90      i.oo      1.30    i. 60      1.90    2.60     3. 30  pounds. 
For  galvanized  iron  add  0.2  pounds  per  square  foot   to  above 
figures. 

Slate  shall  be  taken  at  a  weight  of  7  pounds  per  square  foot 
for  3-16"  -slate  6"  x  12",  and  8.25  pounds  per  square  foot  for 
3-16"  slate  I2"x24",  and  proportionately  for  other  sizes. 

Sheeting  of  dry  pine  boards  at  three  pounds  per"  foot  board 
measure. 

Plastered  ceiling  hung  below  at  not  less  than  10  pounds  per 
square  foot. 

The  exact  weight  of  purlins  shall  be  calculated. 

9.  The    weight  of   Fink  roof  trusses   up   to  200  feet  span 
may  be  calculated  by  the  following  formulas,  for  preliminary  value. 

w=.c6  s-j-,6,  for  heavy  loads. 
w=.Q4  S+.4,  for  light  loads.        (40,  45.) 
s=span  in  feet.      w= weight  per  hor.  sq.  ft.  in  pounds. 

10.  Mill  buildings,  or  any  that  are  subject  to  corrosive  action 
of  gases,  shall  have  all  the  above  loads  increased  25  per  cent. 

11.  Buildings  or  parts  of   buildings   subject    to  strains   from 
machinery  or  other  loads  not   mentioned,   shall  have  the   proper 
allowance  made. 

12.  No  roof  shall,  however,  be  calculated  for  a  less  load  than 
30  pounds  per  horizontal  square  foot. 


Weight  of 
Trusses 


Increase  of 
Loads. 


Minimum 
Load. 


UNIT  STRAINS. 

Iron. 
Tension  only.     j^.    Shapes,  net  section     ,     .     .     . 

Bars 14000 

Bottom  flanges  of  rolled  beams 
Laterals  of  angles,  net  section  . 
Laterals  of  bar 18000 


Soft-Medium. 

Steel 
15000 
17000 
15000 
2000O 


(57) 


(57) 

uo 


Compression 
only. 


Flanges. 


"Combined. 


14.  Flat  ends  and  fixed  ends  .     ,     ,     .     .         12500^500— 

f 

/=length  in  feet  c.  to  c.  of  connections. 

r— least  radius  of  gyration  in  inches.  (59) 

15.  Top  flanges  of  built  girders   shall  have  the  same   gross 
area  as  tension  flanges.         (24) 

16.  Members  subject  to  transverse   loading   in   addition    to 
direct  strain,  such  as  rafters,  and  posts  having  knee  braces   con- 
nected to  them,  shall  be  considered  as  fixed  at  the  ends   in   rivit- 
ed  work,  and  shall  be  proportioned  by  the  following  formulae,  and 
the  unit  strain  in  extreme  fibre  shall  not  exceed  for  soft  medium 
steel:  15000 


Ma  P 

^  _  _  _i_  _  , 

I  A  (52,  62.) 

5  =Strain  per  square  inch  in  extreme  fibre. 

M  —Moment  of  transverse  force  in  inch  pounds, 

n  —Distance  center  of  gravity  to  top  or  bottom  of  final  section 

in  inches. 

I    —Final  moment  of  inertia. 
P  -Direct  load. 

A  —Final  area. 

Soft-  Medium 
Soft  Steel.  Steel.  Sheari 

17.  Pins  and  rivets     .....  10000  (57) 
Web  plates      ......                          7000 

18.  On  ciia.  of  pins  and  rivet  holes  20000  20000       (57)  * 


19.  Extreme  fibre  of  pins    .     .     .  25000 
Extreme  fibre  of  purlins     .     .  15000       (49) 

20.  Lateral  connections  will  have  25   per   cent  greater   unit 
strains  than  above. 

21.  Bolts  may  be  used  for  field  connections  at  two-thirds  of  Bolts- 
rivet  values.        (17,  18.) 

TIMBER   PURLINS 

22.  In  purlins  of  yellow  pine,   southern  pine  or    white  oak,  Timber- 
the  extreme  fibre  strain  shall  not  exceed   1200   Ibs.  sq.  iri.   (50) 

PLATE  GIRDERS. 

23.  The  length  of  span  shall  be  considered  as  the  distance  Girders- 
from,  center   to  center  of  end   bearings   when   girders  rest  on 
bottom    flange,  and  from  end  to  end  when  fastened    between 
columns  by  connection  angles. 

24.  The  compression  flanges  shall   be  stayed  transversely  Fian£es- 
when  their  length  'is  more  than  thirty  times  their  width.          (15) 

One-sixth  of  the  web  shall  be  included  as  flange  area,  provided 
proper  horizontal  splices  are  made  at  web  joints. 

25.  All  web  plates  shall  be  stiffened  at  the  inner  and  outer  stiffeners. 
edges  of  the  end  bearings  and  at  all  points  of  local  concentrated 
loading. 

Intermediate  stiffeners   shall   be   used   provided  the  shearing 
strain  per  square  inch  exceeds  that  given  by  the  formula: 
15000 

d*  d=  Clear  dist.  between  flange  angles  in  inches. 

i  -|  ---  •-       t—  Thickness  of  web  in  inches. 
3000/2 

CORRUGATED  IRON  COVERING. 

26.  Corrugated  iron  shall  generally  be   of  2^  inch   corruga- 
tions,  and  the  gage  in  U.  S.  standard   shall   be  shown   on   strain 
sheet, 


27.  The   span    or    distance  center   to  center  of  roof  purlins 
shall  not  exceed  that  given  in  the  following  table: 

27  gage  .  .  .  2'— o"  20  gage  .  .  .  4'— 6" 

26  gage  ..  .  .  2'— 6"  iSgage  .  .  .  $'—o" 

24  gage  .  .  .  3'— o"  16  gage  ,  .     ,  5'— 6" 

22  gage  .  .  .  4'— o"                                            (48) 

28.  All  corrugated  iron    shall  be  laid  with  one  corrugation 
side  lap,  and  not  less  than  four  inches  end  lap,  generally  with 
six  inches  end  lap.  (32) 

29.  AH  valleys  or  junctions  shall   have  flashing  extending  at 
least  12  inches  under  the  corrugated  iron,or  12  inches  above  line 
where  water  will  stand.  (35,  36.) 

30.  All  ridges  shall  have  roll  cap  securely  fastened  over  the 
corrugated  iron. 

Fastenings  3^  Corrugated  iron  shall  preferably  be  secured  to  the  purlin 
by  galvanized  straps  of  not  less  than  five-eighths  of  an  inch  wide 
by  No.  18  gage;  these  shall  pass  completely  around  the  purlin, 
and  have  each  end  riveted  to  the  sheet.  There  shall  be  at  least 
two  fastenings  on  each  purlin  for  each  sheet. 

32.  The  side  laps  shall  be  riveted  with  six  pound  rivets  not 
more  than  six  inches  apart.  (28.) 

Finish  Anffie  ^$.  At  the  gable  ends  the  corrugated  iron  shall  be  securely 
fastened  down  on  the  roof,  to  a  finish  angle  or  channel,  connect- 
ed to  the  end  of  the  roof  purlins. 

VENTILATORS  AND  LOUVRES. 

Ventilators 

34.  Ventilators  shall  be  provided  and  located  so  as  to  properly 
ventilate  the  building.  They  shal!  have  a  net  area  of  openings 
for  each  100  square  feet  of  floor  surface  of  not  less  than  one- 
half  a  square  foot  for  machine  shops,  of  not  less  than  five  square 
feet  for  mill  buildings  and  not  less  than  seven  square  feet  for 
forge  shops. 

louvres  Louvres  shall  be  provided  in  ventilators,  if  necessary,  of  such 
form  as  to  prevent  the  blowing  in  of  snow  or  storm  watet,  and  of 
a  stiff  enough  section  not  to  sag  below  hoizontal  and  appear  un- 
sightly. They  shall  be  not  less  than  No.  16  gage  galvanized 
for  flat  louvres*  and  No.  20  gage  galvanized  for  corrugated  lou- 
vres. 

LIGHTING. 

windows  35.  Windows  shall  be  provided  in  the  sides  and  clearstory  or 
ventilator  of  a  surface  equal  to  not  less  than  10  per  cent  of  the 
entire  exterior  surface  of  the  buildings,  in  mill  buildings,  and  of 
not  less  than  20  per  cent  in  machine  .shops  or  similiar  build- 
ings. (29) 

Skylights  36.  At  least  half  of  the  lighting  specified  shall  preferably 
be  in  the  form  of  sky  lights  of  some  form  of  construction  which 
shall  entirely  prohibit  leaking.  (29) 


5 
DETAILS  OF  CONSTRUCTION. 

37.  All   tension    members  shall   preferably   be   composed   of  Tension  Mem- 
angles  or  shapes  with  the  object  of  stiffness.  bers* 

38.  All  joints  shall  have  full  splices  and  not   rely  on   gussets. 

(650 

39.  All  main  members  shall  preferably  be  made  of  two  angles, 
back  to  back,  two  angles  and  one  plate,  or  four  angles  laced.  (67.) 

40.  Secondary  members  shall  preferably   be'  made  of  sym- 
metrical sections. 

41.  Long  laterals  or  sway  rods   may  be   made   of  bar,  with 
sleeve  nut  adjustment,  to  facilitate  erection. 

42.  Members  having  such  a  length  as  to  cause  them   to  sag 
shall  be  held  up  by  sag  ties  of  angles,  properly  spaced. 

43.  Rafters  shall   preferably   be  made    of  two  angles,   two  Compression 
angles  and  one  plate,  or  of  such  form  as  to  allow  of  easy  connec- 
tion for  web  members.     (65.) 

44.  All  other  compression  members,   except  sub-struts,  shall 
be  composed  of  sections  symmetrically  disposed.     (65.) 

45.  Sub-struts  shall  preferably   be   made  of  symmetrical  sec- 
tions. 

46.  The  trusses  shall  be  spaced,  if  possible,  at  such  distances  Purlin9- 
apart  as  to  allow  of  single  pieces  of  shape   iron   being  used  for 
purlins,  trussed  purlins  being  avoided,  if  possible.      Purlins  shall 
preferably  be  composed  of  single  angles,  with  the  long  leg  verti- 
cal and  the  back  toward  the  peak  of  the  roof. 

47.  Purlins  shall   be   attached   to  the  rafters  or  columns  by 
clips,  with  at  least  two  rivets  in  rafter  and  two  holes  for  each  end 
of  each  purlin. 

48.  Roof  purlins  shall  be  spaced  at  distances   apart  not  to  ex- 
ceed the  span  given  under  the  head  of  Corrugated  Iron.     (27.) 

49.  Purlins  extending  in  one  piece  over  two  or  more  panels, 
laid  to  break  joint,  and  riveted  at  ends,  may   be  figured   as  con- 
tinuous. 

50.  Timber  purlins,  if  used,  shall   be  attached  in  the  same 
manner  as  steel  purlins. 

51.  Sway  bracing  shall  be  introduced  at  such   points  as  is  sway  Bracing- 
necessary  to  insure  ease  of  erection  and  sufficient  transverse  and 
longitudinal  strength.     (41.) 

52.  All  such  strains  shall  preferably  be  carried  to  the  founda- 
tion direct,  but  may  be  accounted  for  by  bending  in  the  columns. 

(62.) 

$3.     Bed  plates  shall   never   be   less  thar    one-half  inch   in  Bed  Plates, 
thickness,  and  shall  be  of  sufficient  thickness   and  size  so  that 
the  pressure  on  masonry  will  not  exceed  300  pounds  per  square 
inch.     Trusses  over  75  feet  span  on  walls  or  masonry  shall  have 
expansion  rollers  if  necessary.     (54.) 


Punching  and 
Reaming1. 


Effective 

Diameter    of 

Rivets. 


Pitch    of 
Rivets. 


Anchor  Bolts.  54.  Each  bearing  plate  shall  be  provided  with  two  anchor 
bolts  of  not  less  than  three-fourths  of  an  inch  in  diameter,  either 
built  into  the  masonry  or  extending  far  enough  into  the  masonry 
to  make  them  effective.  (53.) 

Punching.  55,     The  diameter  of  the  punch  shall  not  exceed  the  diamter 

of  the  rivet,  nor  the  diameter  of  the  die  exceed  the   diameter  of 
the  punch  by  more  than  one-sixteenth  of  an  inch.     (56.) 

56.  All  rivet  holes  in  steel  may  be  punched,  and  in  case  holes 
do  not  match  in  assembled   members  they  shall  be  reamed  out 
with  power  reamers.     (71.) 

57.  The  effective  diameter  of  the  driven   rivet  shall   be  as- 
sumed the  same  as  before  driving,  and  in   making  deductions  for 
rivet  holes  in  tension   members,   the   hole  will  be  assumed  one 
eighth  of  an  inch  larger  than  the  undriven  rivet.    (13,17.) 

58.  The  pitch  of  rivets  shall  not  exceed   twenty  times  the 
thickness  of  the  plate  in  the   line  of  strain,  nor  forty  times  the 
thickness  at  right  angles  to  the  line  of  strain.     It  shall  never  be 
less  than  three  diameters  of  the1  rivet.     At  the  ends  of  compres- 
sion members  it  shall  not  exceed  four  diameters  of  the  rivet  for  a 
length  equal  to  the  width  of  the  members. 

$9.     No  compression  member  shall  have  a  length  exceeding 
fifty  times  its  least  width,  unless   its   unit    strain   is   reduced 
accordingly.  (14-) 

60.  Laced  compression  members  shall  be  stayed  at  the  ends 
by  batten  plates  having  a  length  not  less  than  the  depth  of  the 
member. 

61.  The  sizes  of  lacing  bars  shall  not  be  less  than  that  given 
in   the  following  table,   when   the  distance  between  the  gage 
lines  is—  (62.) 

6"  or  less  than    8"  . 

8"  or  less  than  10"  . 

10"  or  less  than  12"  .    . 

12"  or  less  than  16"  .    . 

16"  or  less  than  20"  . 

20"  or  less  than  24"  .    . 
24"  or  above  of  angles. 

They  shall  generally  be  inclined  at  45  degress  to  the  axis  of 
the  member,  but  shall  not  be  spaced  so  as  to  reduce  the  strength 
of  the  member  as  a  whole. 

62.  Where  laced  members  are  subjected  to  bending,  the  size 
of  lacing  bars  or  angles  shall  be  calculated  or  a  solid  Veb  plate 
used.     (13,  14,  61.) 

63.  All  rods  having  screw  ends  shall  be  upset  to  standard  size, 
or  have  due  allowance  made. 

64.  No.  metal  of  less  thickness  than   ^   inch  shall  be  used, 
except  as  fillers,  and  no  angles  of  less  than  2  inch  leg.     A  varia- 
tion of  3  per   cent  shall  be  allowable  in  the  weight  or  cross  sec- 
tion of  material. 


I  1-4"  x  1-4" 

I    I-2"X  1-4" 

1  3-4"  x  5-16" 
2"         x  3-8" 

2  1-4"  x  7-16" 


WORKMANSHIP. 

65.  All  workmanship  shall  be  first  class  in  every  particular. 
All  abutting  surfaces  of  compression   members,  except  where 
the  joints  are  fully  spliced,  must  be  planed  to  even  bearing 
so  as  to  give  close  contact  throughout.        (38.) 

66.  All  planed  or  turned  surfaces  left  exposed  must  be  pro- 
tected by  white  lead  and  tallow.        (89) 

67.  Rivet  holes  for  splices  must  be  so  accurately  spaced  that  Rivet8 
the  holes  will,  come  exactly  opposite   when  the  members  are 
brought  into  position  for  driving  rivets,  or  else  reamed  out. 

(38,  70,  71.) 

68.  Rivets  must  completely  fill  the  holes  and  have  full  heads 
concentric  with  the  rivet  holes.  They  shall  have  full  contact  with 
the  surface,  or  b£  countersunk  when  so  required,   and  shall  be 
machine  driven  When  possible.     Rivets  must  not  be  used  in 
direct  tension. 

69.  Built  members  when  finished  must  be  free  from  twists, 
open  joints  or  other  defects.  (65.) 

70.  Drift  pins  must  only   be   used  for  bringing  the  pieces  to- Drillln** 
gether,  and  they   must  not  be  driven  so  hard  as  to  distort  the 
metal.     (71.) 

71.  When  holes  need   enlarging,    it  must  be  done  by  ream-  Rcami°£- 
ing  and  not  by  drifting.     (70.) 

72.  The  decision  of  the  engineer  or  architect  shall  control  as  Drawings  and 
as  to  the  interpretation  of  the  drawings  and  specifications  during  speclfi< 
the  progress  of  the  work.     But    this    shall    not    deprive  the 
contractor  of  right  of  redress  after  work  is  completed,  if  the  de- 
cision shall  be  proven  wrong,     (i,  91,95.) 

QUALITY  OF  MATERIAL. 

WROUGHT  IRON 

73.  All  wrought  iron   must  be  tough,  ductile,  fibrous  and  of  c*a.r*c*er  and 
uniform  quality.    Finished    bars  must    be  thoroughly  welded 

during  the  rolling,  and  be  straight,  smooth  and  free  from  in- 
jurious seams,  blisters,  buckles,  cracks  or  imperfect  edges. 

74.  No  one  process  of  manufacture  is  preferred  over  another,  Manufacture, 
provided  the  material  complies  with  this  specification. 

75.  For  tension  tests  the  test  piece  shall  have  as  near  one- standard  Test 
half  square  inch  of  sectional  area  as  possible,  and  a  length  of  at     Pleces> 
least  8  inches  with  uniform  section,  for  determining  the  elongation. 

76.  The  elastic  limit  shall  be  not  less  than  26,000  pounds  per  Elastic  Limit 
square  inch  for  all  classes  of  iron. 

77.  Standard  test  pieces  from  iron   having  a  section  of  4^  Teasion  Iron 
square  inches  or  less  shall  show  an  ultimate  strength  of  not  less 

than  50,000  pounds  per  square  inch  and  an  elongation  in  8  inches 
of  not  less  than  18  per  cent. 


8 

78.  Standard  test  pieces  from  bars  of  more  than  4^  square 
inches  section   will   be  allowed  a  reduction   of   500  pounds  for 
each  additional  square  inch   of  section,   provided  the    ultimate 
strength  does  not  fall  below  48,000  pounds  or  the  elongation  in 
8  inches  below  15  per  cent. 

79.  All  iron  for  tension   members   must  bend  cold  through 
90  degrees  to  a  curve   whose  diameter   is  not  over   twice  the 
thickness  of  the  piece,  without  cracking. 

80.  Not  less  than  one  sample  out  of  three  shall  bend  cold  to 
this  curve  through  180  degrees,  without  cracking. 

81.  When  nicked  on  one  side  and  bent  by  a  blow  from  a 
sledge,  the  fracture  must  be  wholly  fibrous. 

STEEL. 

Manufacture.  82.  Steel  made  either  by  the  Bessemer  or  Open  Hearth  pro- 
cess of  manufacture  shall  be  acceptable. 

83*  Test  Pieces  for  tension  and  bending  tests  shall  have  as 
near  one-half  square  inch  of  sectional  area  as  possible  and  a 
length  of  at  least  8  inches  with  uniform  section,  for  determiming 
elongation. 

84.  One  test  piece  for  tension  and  one  for  bending  are  to  be 
taken  from  each  heat  or  blow  of  finished  material. 

Finish..  85.    Finished  bars  must  be  free  from  flaws,  cracks  or  injurious 

seams  and  have  a  first-class  finish. 

Grades  gof^  g£t  Steel  of  soft  and  soft-medium  grades  only  are  to  be  used, 
the  soft  steel  for  rivets  and  offset  or  bent  angles  or  plates,  and 
soft-medium  for  all  other  parts  where  iron  is  not  optional. 

Phosphorus    The  phosphorus  shall  never  exceed  in  any  steel  0.08  per  cent., 
ndLimuphnr  nor  the  sulphur  0.04  per  cent.      (56.) 

soft  steei.  87.  Standard  test  pieces  of  finished  material  shall  have  an 
ultimate  strength  of  from  50,000  to  60,000  pounds  per  square 
inch;  an  elastic  limit  of  one-half  the  ultimate  strength;  an 
elongation  in  8  inches  of  not  less  than  25  per  cent;  and  a 
reduction  of  area  at  fracture  of  not  less  than  50  per  cent. 
Samples  to  bend  cold  180  degrees  flat  on  itself,  without  sign  of 
fracture  on  the  outside  bent  portion. 

soft-Medium  88.  Standard  test  pieces  of  finished  material  shall  have  an 
steei.  ultimate  strength  of  from  55,000  to  65,000  pounds  per  square 
inch;  elastic  limit  not  less  than  one-half  the  ultimate  strength; 
an  elongation  in  8  inches  of  not  less  than  25  per  cent.;  and  a 
deduction  of  area  at  fracture  of  not  less  than  50  per  cent.  Samples 
to  bend  cold  180  degrees  to  a  diameter  equal  to  the  thickness  of 
the  sample  without  crack  or  flaw  on  fhe  outside  of  the  bent 
portion. 

PAINTING. 

Painting.  89.  All  iron  or  steel  framing  and  all  corrugated  iron,  unless 
galvanized,  shall  have  one  coat  of  pure  lead  paint  before  leaving 
the  shop;  all  surfaces  in  contact  shall  have  one  heavy 


9 

coat  of  pure  lead  paint  before  assembling,  and  all  planed  or 
turned  surfaces  shall  be  coated  with  white  lead  and  tallow  (66.) 

90.  Parts  difficult  of  access  after    erectiion  shall  have  two 
coats  of  pure  lead  paint  at  the  shop. 

91.  After  erection  all  the  work  except  galvanized  iron  shall 
receive  one  coat  of  pure  lead  paint  of  such  shade  as  the  engineer 
or  architect  may  select,  and  it  shall  be  thoroughly  and  evenly 
applied.    (72,95-) 

ERECTION. 

92.  The  contractor  will  furnish  all  tools,  derricks  or  staging  Erection, 
and  material  of  every  description  for  the  erection  of  the  whole  or 

such  portions  of  the  work  as  are  included  in  the  contract,  and 
remove  the  same  when  the  work  is  completed,  leaving  the  prem- 
ises as  free  from  rubbish  or  obstruction  as  when  the  erection  was 
commenced. 

93.  The  contractor  shall  assume  all  risks  from  storms  or  acci- 
dents to  the  work,  unless  caused  by  the  negligence  or  interfer- 
ence of  the  owner  or  his  employees;  also  all  damage  to  persons 
and    properties  and  casualties  of   every    description,   until  the 
final  acceptance  of  the  completed  structure. 

94.  The  contractor  shall  comply  with  all  ordinances  or  reg- 
ulations of  the  authorities  having  jurisdiction  over  the  premises  or 
abutting  premises. 

95.  The  erection  is  to  be  carried  on  subject  to  the  approval 
and  inspection  of  the  engineer  or  architect,  and  it  is  to  be  com- 
pleted   to    his    satisfaction    and    in    full    accordance    with  the 
contract.  (72,91.) 


^7\BRA 

OF  THE 

UNIVtK3ITY 

OF 


10 


COEFFICIENTS    FOR    ROOF    TRUSSES. 


s  -  — 


?rcx\V  ~\vtxss. 
P<xwe\s.     P 


n  =    s  =     * 

h        pitch 


s=span,          h=height.  P=  panel  load. 

•f  compression.  — tension.    Strain  in  member  =  Px  coefficient. 

Load  on  wall  or  column  =  Reaction+o.gP. 


PRATT    TRUSS,    EIGHT    PANELS. 


Member 

*=3 

W=4 

*=5 

General  Formulae. 

Ba-Cb 

6.31 

7.83 

9.42 

XP 

4-i.75vV  4-  4 

Dd 

5.41 

6.71 

8.08 

+1.PS*W4 

XP 

Ef 

4.51 

5-59 

6.73 

4-I.25VV  4.  4 

XP 

La 

5.25 

7.00 

8.75 

—1.75  » 

XP 

Lc 

4.50 

6.00 

7.50 

—  1.50  n 

XP 

Le 

3-75 

5.00 

6.25 

—  1.25  n 

XP 

Lg 

3.00 

4.00 

5.00 

—i.oon 

XP 

ab 

1.  00 

1.  00 

1.  00 

4-1.00 

XP 

cd 

1.50 

1.50 

1.50 

+  1.50 

XP 

ef 

2.OO 

2.00 

2.OO 

4-2.00 

XP 

be 

1.25 

I.4I 

1.  60 

—  o>25\/n*-i-i6 

XP 

de 

1.68 

1.  80 

1.95 

—0.25^24-36 

XP 

fg 

2.14 

2.24 

2.36 

—0.25^34-64 

XP 

PRATT  TRUSS,  FOUR  PANELS. 


ii 


I 

General   Formula?. 

AAember 

?z=3 

11=4 

n=$ 

Ba-Cb 

2.70 

3-35 

4.04 

xP 

+o.75v/;*2+4 

La 

2.25 

3.00 

3-75 

—0.75  n 

XP 

Lc 

1.50 

2.00 

2.50 

—  0.50  n 

xP 

ab 

I.OO 

I.OO 

I.OO 

+  I.OO 

xP 

be 

1.25 

I.4I 

i.  60 

-0.25v/w2+l6 

xP 

PRATT  TRUSS,  TWELVE  PANELS. 


Member 

0=3 

n=4 

«=5 

General  Formula?. 

Ba-Cb 

9.92 

12.30 

14.81 

+2.75x/^+? 

XP 

Dd 

9.01 

11.18 

13.46 

+  2.r>Ov/;z2+4 

XP 

Ef 

8.  n 

10.  06 

12.12 

+  2.25x/^+^ 

XP 

Fh 

7.21 

8.94 

10.77 

+  2.00x/w2+4 

xP 

Gk 

6.31 

7.83 

9.42 

4-i-75x/«*.+4 

XP 

La 

8.25 

11.00 

13-75 

—2.75/3 

XP 

Lc 

7.50 

IO.OO 

12.50 

—  2.5077 

XP 

Le 

6.75 

9.00 

11.25 

—  2.25« 

XP 

Lg 

6.00 

8.00 

IO.OO 

—  2.OOH 

XP 

Li 

5-25 

7.00 

8.75 

-1.75* 

XP 

LI 

4.50 

6.00 

7.50 

—  I.50H 

xP 

ab 

I.OO 

I.OO 

I.OO 

+  1.00 

XP 

cd 

1.50 

1.50 

1.50 

+  1.50 

xP 

ef 

2.OO 

2.OO 

2.00 

+  2.OO 

xP 

gh 

2.50 

2.50 

2.50 

+  2.50 

xP 

ik 

3-00 

3.00 

3  oo 

+  3-00 

xP 

be 

1.25 

1.41 

i.  60 

—  o.25vV+i6 

xP 

de 

i.68 

1.  80 

1.95 

—  0.25^2+36 

xP 

fg 

2.14 

2.24 

2.36 

-o  25v/,lH:6^ 

xP 

hi 

2.61 

2.69 

2.80 

—  o.25vV-fIOo~ 

XP 

kl 

3.09 

3.16 

3.25 

—  o.25vV+i44 

XP 

PRATT    TRUSS,     SIX    PANELS. 


Member 

m 

*=4 

*=S 

General  Formulae. 

Ba-Cb 

4.51 

5-59 

6.73 

XP 

4-i.25v/tf*4-4 

Dd 

3.61 

-4-47 

5-39 

4-l.OOvV4-4 

XP 

La 

3.75 

5.00 

6.25 

—  1,25  n 

XP 

Lc 

3.00 

4.00 

5.00 

—  i.oo  n 

XP 

Le 

2.25 

3.00 

3-75 

—0.75  n 

XP 

ab 

I.OO 

I.OO 

I.OO 

4-1.00 

XP 

cd 

1.50 

1.50 

1,50 

4-1.50 

XP 

be 

t 

1.25 

1,41 

1.60 

-o.25v/^H[6 

XP 

de 

i»68 

i.  80 

1.95 

—  O.25v/fl2_|-  36              xP 

PRATT    TRUSS,    TEN     PANELS. 


Member 

n=, 

«=4 

if  =5 

General  Formulae. 

Ba-Cb 

8.11 

IO.O6 

12.12 

4-2.25^/^4^ 

XP 

Dd 

7.21 

8.94 

10.77 

4-2.oo^/fl2_f_4 

XP 

Ef 

6.31 

7.83. 

9.42 

+  t.7$</w+j 

XP 

Fh 

5.41 

6.71 

8.08 

-}-i.5Ov/fl2_j_4 

XP 

La 

6.75 

9.00 

11.25 

—2.257* 

XP 

Lc 

6.00 

8.00 

IO.OO 

—  2.0OW 

XP 

Le 

-     5-25 

7.00 

8.75 

—  1.757* 

XP 

Lg 

4.50 

6.00 

7.50 

—  1.50^ 

XP 

Li 

3-75 

5.00 

6.25 

—  1.2511 

xP 

ab 

1.00 

I.OO 

I.OO 

-j-I.OO 

XP 

cd 

1.50 

1.50 

1.50 

+1.50 

xP 

ef 

2.OO 

2.OO 

2.0O 

4-  2.  CO 

XP 

gh 

2.50 

2.50 

2.5O 

4-2.50 

XP 

be 

1.25 

I.4I 

1.60 

-o.25x/^4:T6 

XP 

de 

1.68 

1,  80 

1.95 

—  o.25v/W2_|_36 

xP 

fg 

2.14 

2.24 

2.36 

-o.25v/^4:6j 

xP 

hi 

2,6l 

2.69 

2.80 

-0.25%/n-fhioo            xP 

COEFFICIENTS    FOR    ROOF    TRUSSES. 


Compound  Fintf  Truss 


Compound   Fan  Truss. 


S  •  span 


s  =  span,  h  ==  height.   P  =  panel  load,  n  =£  =  pjj^    -|-  compression.  — tension. 
Strain  in  member  =  P  X  coefficient.     Load  on  wall  orcolumn~=  Reaction  -]-o.5  P 

COMPOUND  •  FINK , TRUSS. 


Member. 


Ba 
La 

ab 

Cb 

be 
Lc 

cd 

De 

ed 


ef 

fe 
Ef 


6.31 
5-25 

0.83 


0-75 
4-50 

1.66 


5.20 

o-75 

3.00 

1-50 
0.83 

2.25 
4-65 


«= 4 


7.83 
7.00 

0.89 
7-38 

1. 00 

6.00 
1.79 

6-93 

I.OO 

4.00 

2.0O 
0.89 
3.00 
6.48 


*=5 


9.42 
8-75 

o-93 


9-05 

1.25 
7-50 

1.86 


8.68 

1.25 
5.00 
2.50 

0-93 
3-75 
8.31 


General  Formulae. 


— \n 


2n 


—  n 


XP 
XP 

XP 

XP 

XP 
XP 

XP 


XP 
XP 
XP 

XP 
XP 
XP 


SIMPLE  FINK  TRUSS. 


Member. 

•**#< 

?  «=4 

:'  £* 

General  Formulae. 

Ba 

2.71 

3-35 

4.04 

+  ^1/^24-4                 XP 

La 

2.25 

3.00 

3-75 

-ft*                            XP 

ab 

0.83 

0.89 

o.93 

f                                                                    v/*  T} 

'    1/7*2  -|-  4 

Cb 

2.15 

2*91 

3-66 

I 

1/w2  -j~  4V/^ 

be 

0-75 

I.OO 

J.25 

—  i/w                           vP 

/^.  rm                                               /\  JL 

Lc 

1.50 

2.00 

2.50 

'1/11                                               V  "P 

—  72^2                                   A  ir 

COMPOUND  FAN  TRUSS. 


Member. 

igj 

«=  4 

n=S 

General  Formulae. 

Ba 
La 

ab—  be 

Cb 

DC 

cd 
Ld 

de 

Ef 

fe 
ei 
Li 

fg-gh 

Gh 
hi 

9.91 

8.25 

o-93 
8.94 

8.80 

1.50 
6-75 

8.25 

1.50 
2.25 
4.50 

7.28 

7.14 
3-75 

12.30 

I  I.OO 

!     1.08 
11.25 
11.40 

2.OO 
9.OO 

2/69 

10.96 

2.0O 
3.00 

6.00 
1.08 

9-93 

1  0.06 
5.00 

14.80 

1.  21 
13.66 

14.07 
2.50 

2-79 

13.69 

2.50 

3-75 
7.50 

1.  21 

12.54 

12.95 
6.25 

i 

/  ~  —  -  \-f-'"    i  •*••'•/  /**  ± 

v  n^  -{~  4 

—  V-«                            X  P 

,  «T/«4+40«2  +  i44 

6  (722+4) 
_|  (s  ini  _|_  x^    v  p 

1                               /i  i  ~J2    1    fy"\      v/'  p 

—  i«                                X  P 
—  In                               XP 

1/W2  +  4 

.  ^  •.  •••/;-  T 

—  i«                               XP 
—  1«                              XP 
—  1»\                              XP 

.  «.1/  ^4  7}-  40^2-}-  144    v 

I          , 

I 

-|«"                             XP 

SIMPLE  FAN  TRUSS. 


Member. 

i«?*3 

£44 

«=5 

General  Formulae. 

Ba 

4-5° 

5-59 

6.73 

i 

La 

375 

5.00 

6.25 

—  j«                                   X  P 

ab  \ 
be  j 

o-93 

1.08 

1.  21 

#l/#4  -f4o;/H-  144  v  P 

6  (732  +  4) 

i 

Cb 

353 

4-55 

S58 

L_                                (  \*\  it*)    [    zT  \        >,,/  T[3 

2l/«2-|-4U 

DC 

3-39 

4.70 

5-9* 

4~7=L=  (f*2-M)     XP 
•na+4 

cd 

1.50 

2.00 

2.50 

T   /    -^                                                                                                    VX     T) 

"r"y^.'» 

Ld 

2.25 

3.00 

375 

•j  /^-                                                  v  "O 
—  74  7*                                             A  r 

STEEL  COLUMN  UNIT  STRAINS.     Q  Q  12500  -  500 


/-*-r 

n  D 

/-7-r 

G  D 

/-4-r 

n  n 

£*-r 

D  D 

3.0 

IIOOO 

7-6 

8700 

12.2 

6400 

16.8 

4100 

.2 

10900 

.8 

8600 

•4 

6300 

17.0 

4000 

•4 

10800 

8.0 

8500 

.6 

6200 

.2 

3900 

.6 

10700 

.2. 

&400 

,8 

6100 

•4 

3800 

.8 

10600 

•4 

8300 

13-0 

6000 

.6 

3700 

4.0 

10500 

.6 

8200 

.2 

5900 

.8 

3600 

.2 

10400 

.8 

8100 

•4 

5800 

18.0 

35°° 

•4 

10300 

9.0 

8000 

.6 

5700 

,2 

3400 

.6 

10200 

.2 

7900 

.8 

5600 

•4 

33oo 

.8 

IOIOO 

•4 

7800 

14.0 

5500- 

.6 

3200 

5-o 

IOOOO 

.6 

7700 

.2 

5400 

.8 

3100 

.2 

9900 

;3 

7600 

•4 

5300 

19.0 

3000 

•4 

9800 

ro.o 

7500 

.6 

5200 

2 

2900 

.6 

9700 

.2 

7400 

.8 

5100 

•4 

2800 

.8 

9600 

•  4 

7300 

15.0 

5000 

.6 

2700 

6.0 

9500 

.$ 

7200 

.2 

4900 

.8 

2600 

.2 

9400 

'.8 

'7100 

.4 

4800 

•20.  o 

2500 

•4 

9300 

li.o 

700O 

.6 

4700 

,2 

2400 

.6 

9200 

.2 

6900 

.8 

4600 

•4 

2300 

8 

9100 

.4 

6800 

16.0 

•4500 

.6 

2200 

7.0 

9000 

.6 

6700 

;.2 

4400 

.8 

2100 

.2 

8900 

.8 

6600 

•4 

4300 

•4 

8800 

12.  0 

6500 

.6 

4200 

SHEARING  AND  BEARING  VALUE  OF  RIVETS. 


Diam.ofRivet 
in  inches. 

Area  of 
Rivet. 

Single 
Shearat 
10000  ft 
pr  eq  in 

Bearing  val.  of  different  thicknesses  of  plato  at  20000  Ibs.  per  so.  in. 
(  —  Diam.  of  Rivet  X  thickness  of  plate  X  20000  Ibs. 

Frac- 
tion. 

.  Deci- 
mal. 

\" 

iV' 

f" 

&" 

\" 

&" 

f" 

IOI6O 
IQ940 
11720 

H" 

¥' 

fy 

W' 

3." 

1*3  // 
if 

i" 

H" 

-5625 
.625 

.6875 

•  75  : 
8125 

.875 
•9375 

.1963 
-2485 
.3068 

.3712 
,-4418 
.5185 
.6013 
.6903 

1960 
2480 
3070 

3710 
4420 
5l8o 
6oiO 
6900 

2500 
2810 
3130 
$440 
3750 
4070 
4380 
4690 

3130 
3520 
3910 
4290 
4690 
5080 
5470 
5850 

3750 

4210 

4690 
5160 
5630 

6090 

6570 
7030 

4920 
5470 

6010 

6560 

7110 

7660 
8200 

6880 
7500 

8I2C7 
8750 
9370 

8440 
9150 
9840 
10550 

12890 

INDEX. 


Acceptance,  72,  95.  Imperfections,  73,  85.  Sways,  41,  51,  52. 

Architect,  72,  91,  95.  Span,  23,  27,  46. 

Anchors,  54.  Joints,  24,  38,  65.  Strain  Sheet,  i,  2,  72. 

Slate,  8. 

Bars,  13,  41,  63,  77,78,  79,  Lacing,  60,  61,  62.  Shapes,  13,  87,  88. 

80,  81,  85,  87,  88.  Lap,  28.  Sag  Ties,  42. 

Battens,  60.  Laterals,  13,  20,  41.  Secondary  Members,  40, 

Bessemer  Steel,  82.  Lateral  Connections,2o,          44,  45. 

Bearing,  18,  53,  65.  41.  Sheeting,  8. 

Beams,  13.  Lighting,  35,  36.  Shearing,  17. 

Bending,  16,  19,  52,62,86,  Loads,  5,6,7,8,9,10,11,  12  Screw,  63. 

Bed  Plates,  53.  Louvres,  34.  Steel,  82,  83,  84,  85,  86, 
Boards,  6.  87,  88, 

Bolts,  21,  54.  Machinery,  n.  Stiffeners,  25. 

Built  Members,  69.  Machine  Shops,i  1,34,35.  Splices,  24,  38,  65,  67. 

Main  Members,39,43,44.  Snow,  34. 

Clips,  31/47.  Masonry,  3,  52,  53,  54.  Snow  Load,  5. 

Corrosion,  10.  .  y  Mill   Buildings,   10,  n,  Soft  Steel,  86,  87. 

Columns,  14,  42,  44.  34,  35.  Soft-Medium  Steel,  86, 

Compression  Members,  14,  Minimum  Loads,  10,  11.          88. 

24,  43,  44,  45,  52,  58,          12.  Sub-Struts,  44,  45. 

59,60,61,65,66,69.  Sulphur,  86. 

Completion,  95.  Offsetting,  86.  Skylights,  36. 

Combined  Strains,  16.  Open  Hearth  Steel,  82. 

Corrugated  Iron,  8,  26,27,  Test  Pieces,    75,  83,  84. 

28,  31,  32,  33-,  89,  91.  Plate  Iron.  87,  88.  Tension  Members,    13, 

Contractor,  72,93,  94.  Painting,  66,  90,  91.  16,24,  37,  38,  3^, 

Planing,  65,  66,  89.  40,  41,  42,  57,  68. 

Damage,  92,  93,  94,  95,  Plaster,  8.  Timber,  22,  50. 

Drawings,  i,  2,  72.  Plate  Girders,  13,  15,17,  Tie  Plates,  60. 

Decisions,  72.  -       23,  24,  25.  Tools,  92. 

Diagram,  i,  2,  72.  Pitch  Roof,  4,  5-'6.  Trusses,  9,  46. 

Dimensions,  3,  23.  Pitch  Rivets,  58,  Turning,  66,  89. 

Drift  Pins,  70,  71.  Pins,  17,  18,  19. 

Process  of  Manuf  'g,  74,  Upsets.  63. 

Elastic  Limit,  76,  87,  88.  82.  Unit  Strains,  13,  14,  15, 

Erection/41,  51,  90,  91,92,  Phosphorus,  86.  X6,  17,  18,  19,  20, 

_     93,  94,  95-  Punching,  55,  56,  57,  58.          21,  22,  59. 

Engineer,  72,  91,  92,93,94.  Purlins,  8,  19,  22,  31,46,  Valleys,  29. 

C1    95-  47,48,49,50.  Variation  in  Weight,  64. 

Elongation,  77,  78,  87,  88,  Purlin  Spacing,  27,  48.  Ventilation,  34, 

Purlin  Clips,  31,  47- 

Falsework  92.  Water,  29;  34- 

Framing,  89.  Rafters,  43.  Webs,  17,  24,  43,  62, 

Flanges,  13,  15,  24.  Reaming,  56,  71.  Weight  Material,  64. 

Flashing,  29.  Redress,  72.  Weight  of  Trusses,  9. 

Field  Connections,  21.  Rivets,  17,  18,55,  56,  57,  Wind,  6,  7. 

Finish  Angle,  33.  58,  67,  68,  69.  Windows,  35. 

Finished  Surfaces,  65.  Rivet  Holes,  55,  56,  57,  Wrought  Iron,  73,    74, 
Foundations,  3,  52,  53,  54-           67,68.  75)  76,,77,  78,  79, 

Foundries,  34.  Ridges,  30,  go   gi. 

Risks,  93. 

Girders,  13,  15,    i7,   23,  Roll  Cap,  30. 

24,  25.  Rollers,  53* 


OF  T.HE 

UN!VLK3ITY 


;Jfj< -Covers  24" HlV       **°'    ->l      k-         "Covers  £4" 

p<- E8"before  Corrugating >|  K 30"before  Corrugating"- 


j  (<W  for  sheets  less  than  £4>]       Note  -  Unsymmetrical  sheets  should 


fer o-- ;-H 


Louvre  bars  at  panel  points 
and  2.^4  for  int.  splice  Corrug  Louvres  require  an  8 
sheet  -  plain  Louvres  7i 


CORRUGATED  IRON, LOUVRES, FLASHING  &c. 


THIS  BOOK  IS  DUE  OK  THE  LAST  DATE 
STAMPED  BELOW 

AN  INITIAL 


YC   13045 


GENERAL  LIBRARY- U.C.  BERKELEY 


Boocmssss 


